If you have configured a Windows Server 2012-based Hyper-V failover cluster CSV and your backup software perform the backup by using snapshots and the Physical Disk resource is moved to another node in the cluster, the Physical Disk resource may fail to come online if the backup of the CSV is in progress. As a result, virtual machines that rely on the CSV may crash.

A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem.